When the pilot is having his heart attack, his right leg spasms and he knocks into the controls and sends the plane in a twist to the right and Brian does not correct this course change for quite some time. It isn't until the nose tilts down after hitting some turbulence that Brian realizes he has to "fly" the plane. Once he gets the hang of keeping the plane level, he tries to use the radio to let someone know about his situation.
He finds that he is out of range and cannot get a clear message to someone so he focuses on flying the plane. He sees a few numbers, thinks 160 is the speed of the plane and that 342 is the heading but he isn't sure. He flies on and then decides to try and find a lake. It isn't long after that that the plane runs out of gas and forces Brian to immediately start searching for a place to set the plane down. He just barely makes it, brushing the trees and then slamming into the lake.
It isn't clear where the lake is and even when the pilot lands there to rescue him at the close of the story the location is not specified.